1. Before you publish: Copyright
Ensure that any agreement with your publisher permits the submission of your manuscript to NIH PubMed Central.
Look up your journal or publisher to see whether it will deposit your article on your behalf.
Review journal or publisher policies before you submit: See NIH-specific publisher policies at the Open Access Directory wiki if you know who publishes your journal; Use the more general Publisher policy database at Sherpa/Romeo, and check the "mandated OA" section of the record.
Use a contract addendum, if the publisher's contract doesn't automatically give you the rights you need to give your publisher notice that your article is subject to the NIH requirement.
Contact AskaLibrarian@jefferson.edu for assistance identifying journal policies.
2. After your article is accepted: Submit your manuscript
Unless you've made arrangements for the publisher to do it, the final version of the manuscript, plus any accompanying files, must be submitted to the NIH Manuscript Submission System (NIHMS).
3. When you prepare NIH applications, proposals, or progress reports: Cite PubMed Central ID numbers.
When your manuscript is submitted to NIH it will receive an NIHMS ID number, and once it is available in PubMed Central, it will be assigned a PMC ID number.